scholarly journals REARRANGEMENT OF THE CONFORMATIONAL STRUCTURE OF POLYAMPHOLYTES ON THE SURFACE OF A METAL NANOWIRE IN A TRANSVERSE MICROWAVE ELECTRIC FIELD

2021 ◽  
Vol 18 (1) ◽  
pp. 16-28
Author(s):  
N. Yu. Kruchinin ◽  

Molecular dynamics has been employed to study the rearrangement of the conformational structure of polyampholytes adsorbed on the surface of a gold nanowire with a periodic change in time of its polarity in the transverse direction at an ultrahigh frequency. The radial distributions of the atomic density of the polypeptide and its angular distributions on the nanowire surface have been calculated. At high temperatures, temporary fluctuations in the conformational structure of the adsorbed polyampholyte polypeptide were observed. In this case, for half the period of the nanowire polarity change, the macrochain conformation changed from dense enveloping of the nanowire to an elongated conformational structure along the dipole moment of the nanowire. At low temperature and the nanowire dipole moment, the swelling of the fringe of the adsorbed polyampholyte was observed with a displacement of most of its links to one side with respect to the plane perpendicular to the direction of the nanowire dipole moment and passing through its axis. At low temperature and high values of the nanowire dipole moment, the polyampholyte polypeptide was desorbed from the nanowire surface. An analytical model of conformational rearrangements of a polyampholyte Gaussian chain in the form of an external field perturbation theory is presented.

2015 ◽  
Vol 41 (11) ◽  
pp. 936-941 ◽  
Author(s):  
A. Yu. Ivanov ◽  
Yu. V. Rubin ◽  
S. A. Egupov ◽  
L. F. Belous ◽  
V. A. Karachevtsev

2011 ◽  
Vol 21 (6) ◽  
pp. 067001 ◽  
Author(s):  
Yuanhui Li ◽  
Quan Xie ◽  
Wei Wang ◽  
Mingxin Zheng ◽  
Hao Zhang ◽  
...  

2018 ◽  
Vol 27 (10) ◽  
pp. 1850086
Author(s):  
A. Abdelsalam ◽  
M. S. El–Nagdy ◽  
A. M. Abdalla ◽  
A. Saber

In this paper, we investigate the possible mechanisms, which are responsible for the production of slow target fragments with energy [Formula: see text][Formula: see text]MeV that are emitted from interactions of [Formula: see text]Si nucleus with emulsion nuclei at energy 14.6[Formula: see text]GeV per nucleon. Angular distributions of slow fragments are compared with the corresponding results from collisions of 1H, 3He, 4He, 7Li and [Formula: see text]C with emulsion at the energy range 2.2–3.7[Formula: see text]A[Formula: see text]GeV. We investigate the effects of both projectile energy and mass number on the angular distributions for slow secondary charged fragments called gray and black track producing particles. The average emission angles are found to be [Formula: see text] and [Formula: see text] for gray and black tracks, respectively. These values are nearly constant for all compared experiments. There are two different mechanisms of gray particle production in forward and backward directions while there is a single symmetric mechanism for black particles in both directions. The temperatures are found to be 58 and 6[Formula: see text]MeV for systems of emissions for gray and black particles, respectively. There are strong effects of target size on those mechanisms. The emission system of these particles becomes slower and shows low temperature with the increase in volume of target nucleus.


2006 ◽  
Vol 963 ◽  
Author(s):  
Loucas Tsakalakos ◽  
Jody Fronheiser ◽  
Larry Rowland ◽  
Mohamed Rahmane ◽  
Michael Larsen ◽  
...  

ABSTRACTPolycrystalline SiC nanowires and composite Si nanowire-SiC nanograin structures have been synthesized using a combined catalytic chemical vapor deposition and carburization method. Si nanowires are grown at low temperature (550-650 C) and subsequently carburized at 1100-1200 C in a methane/hydrogen or propane/hydrogen environment. Thermochemical calculations showed that the Si carburization is thermodynamically favorable over a wide tempareture range, whereas our studies showed that the Si nanowire carburization is kinetically limited below ∼1100 °C. Partially carburized nanowires contained distinct SiC nanosized grains on the Si nanowire surface, whereas fully carburized nanowires were polycrystalline 3C SiC with grain sizes of ∼ 50-100 nm.


Nuclear alinement of the isotopes 149 Pm and 151 Pm has been obtained in the ethyl sulphate and double nitrate lattices by the low-temperature alinement method. The anisotropic γ -ray angular distributions were used to detect this alinement. The results suggest that in the double-nitrate lattice the lowest ionic state of Pm 3+ is a singlet and that alinement arises through a ‘pseudo-quadrupole’ mechanism. Beta and γ -spectroscopy measurementsshow that the 285 keV γ -ray in the decay of 149 Pm is associated with a weak (1.8 ± 0.3 %) β -group of maximum energy 0.77 ± 0.05 MeV. The alinement measurements are consistent with this 285 keV γ -ray being principally M 1 with the spin of the excited state being 5/2 or 9/2.


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